NFSv4.1 Implementation ID Domain

configname: CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN

Linux Kernel Configuration
└─>File systems
└─>Network File Systems
└─>NFSv4.1 Implementation ID Domain
In linux kernel since version 3.1 (release Date: 2011-10-24)  
This option defines the domain portion of the implementation ID that
may be sent in the NFS exchange_id operation. The value must be in
the format of a DNS domain name and should be set to the DNS domain
name of the distribution.
If the NFS client is unchanged from the upstream kernel, this
option should be set to the default "kernel.org".